Rice Wireless Experts Tap Unused Tv Spectrum

Researchers at Rice University have developed a multiuser, multiantenna transmission scheme that makes use of the unused portion of the UHF radio spectrum.

Credit: Jeff Fitlow/Rice University

Rice University researchers have developed a multiuser, multiantenna transmission scheme designed to make use of the unused portion of the UHF radio spectrum that has historically been reserved for TV broadcasts.

The researchers say the scheme combines several proven technologies that already are widely used in wireless data transmission. One technology is multiple-input, multiple-output (MIMO), a scheme that employs multiple antennae to boost data rates without the need for additional channels or transmitter power. "Imagine that the Wi-Fi access point in your home or office sends data down a 100-lane highway, but it's only one mile long," Rice graduate student Narendra Anand. "For UHF, the highway is 100 miles long but only three or four lanes wide."

The system, which is based on the wireless open-access research platform, enabled the researchers to perform a side-by-side comparison of multiuser MIMO for UHF and for both 2.4 gigahertz and 5.8 gigahertz Wi-Fi. "Based on over-the-air experiments in a range of indoor and outdoor operating environments, we found that UHF-band multiuser MIMO compared favorably and produced high spectral efficiency as well as low-overhead wireless access," says Rice professor Edward Knightly.

The researchers presented their findings this week at ACM's MobiCom 2014 conference in Maui, HI.